If OD ever pokes his head back in here I know he would recommend the three kannons.
Hardy har har Skeetergod. But yes, I always heavily advice Kannons, and have done so since before the current edition, which is BOFFO for Artillery by the way.
But since I'm a latecomer to this rodeo, I'll only be commenting on the last posted list from Grimdakka.
To which end I'll say good luck and Waaagh on, it looks like a dead 'ard list.
This next part you are free of course to take, or leave. Personally I have a problem with IC Bikes joining units who are on foot. It's something that I feel is wrong, and shouldn't be allowed. Maybe there used to be a rule preventing this, and my opinion is rooted in that, or maybe it's the inner Speed Freak in me that's just perturbed by the concept of a speed loving lunatic walking his bike with a green sea for the equivalent of a half mile before actually getting out of first gear.
Like I said, you can take or leave that at your own discretion, there is certainly nothing in the current rulebook that would negate the ability to put an IC with a Bike, Jetbike, Jetpack, Jumppack, or Calvary mount with a unit that is not similarly equipped.
What I can say is that instead of two of them, I'd rather have a KFF Mek (maybe even two) to help protect the boyz from incoming fire as they progress up the battlefield. I really wouldn't want my Warlord to be engaging in the suicidal Boss Biker Bomb tactic, as I'm just not in the habit of giving my opponent a free Victory Point. Don't get me wrong, I'm not a win at all costs tourney style of player, but I also generally don't want to hand my opponent victory either. Its gotta be fun for both players, and I know for me its never fun when I win a game outright with no challenge.
One of the big benefits of a KFF Mek(s) is overall cheaper HQ section, which gives you some more points to spend in the rest of the army, afterall the HQ section isn't where Orks get things done in, Orks have some amazing units that even after 6 years since the dex dropped can hold their own, but they aren't really in the HQ section. If you replace just one of those Biker Bosses with a basic KFF Mek with Cybork and Eavy Armor (to help ward off Precision Shots and failed Look Out Sirs) you'd save 55 points, which you could handily use to plop in 3 Nobz with Bosspoles in your Shoota units and have some change left over for a couple of Big Shootas.
Speaking of which, those Nobz are still in my opinion one of the most important and integral elements of an Ork Horde. Yes Mob Rule can and will keep a unit going thru some horrible casualties, but it only goes so far; to get the best bang for the buck with your Troop Choices/Scoring Units, you kinda need Bosspole Nobz. Small price to pay, which is slightly a pun because they're fairly cheap in points, and you don't have to loose a Shoota to grab one for your unit of Shootaboyz. He then can't take a Pk, but it seems like your not too focused on wanting those in the first place.
All that being said, I do think your current list can certainly net some wins, and to that end if you keep it the same or alter your list my overall wellwishing is this: Waaaagh On!
Peace
~OD